In recent years, use of face detection processing that classifies image data of a video image obtained by imaging into characteristic parts (for example, a face) of a person has been promoted in various fields. Performing processing at a high speed by reducing an amount of calculation as well as a face discrimination accuracy are important in face detection processing.
Here, as prior art relating to the face detection processing in which the amount of calculation is reduced and the processing speed is increased, for example, a face detection device disclosed in PTL 1 is suggested.
The face detection device disclosed in PTL 1 switches a face detection mode in which a face detection area is set according to a designation by a user and sets a face type template of a size corresponding to the face detection mode. The face detection device performs template matching processing on a face detection area range using the set face type template.
In the face detection device, the minimum value and maximum value of the size of the face type template is determined for each face detection mode in advance. In a case where a face cannot be detected in the template matching processing using the face type template of the maximum size, the face detection device performs the template matching processing using the face type template of the next largest size in the same face detection mode.